Outside pipe cutter



1941- a. A. LowREY 2,229,331

ouwsm': mE CUTTER:

7 Filed Feb. 15, 1939 Patented Jan. 21, 194l UNITED; STATES PATENT OFFICE 7 This invention relatesto an outside pipe cutter.

An object of the invention -is to provide a cutting tool-shaped to be .telescoped over a pipe Y. stuck. in a well bore andhaving meansfor cut-. ting of a section of thestuck pipe, by rotating the tool, and. including. means for withdrawing the cut off section from the well uponwithdrawal of the tool.

Another object of the invention is to provide an outside cuttingtoolcomprising a body with inwardly movable cutting means therein normally held retracted; an actuator within the body, yieldable means 'for holding the actuator inactive, and" means engageable underneath a coupling on' thepipe whereby, upon upward movementof the cutter body, and cutting means;

the actuator'will'be held in stationary position to move the cutting means inwardly into cutting relationwith the pipewhereupon the pipe will be severed upon rotation of the tool.

It is anotherobject of the invention to provide a cutting tool of the character described wherein the cutting means andcutting actuator will re-' turn to inactive positions upon release of the upward tension ont-he operating string.

With'the above and other objects in view the invention has particular relation to certain novel" features of construction, operation and arrangement of parts, an example of which'is given in 30, this specification and illustrated in the accompanying drawing, wherein:

Figure 1 shows avertical, sectional view of the tool telescoped'over a' pipe to be cut;

Figure 2 shows a cross-sectional view taken on the line 22 of Figure 1.

Figure 3 shows a fragmentary, vertical, sectional view showing the cutters in active, or operating position, and

Figure 4 shows a cross-sectional view taken on the line 4-4 of Figure 3.

Referring now more particularly to the drawing wherein like numerals of reference designate the same parts in each of the figures, the numerals I, la designate lower and upper sectiions of a tubular cutter body shown connected together by threads and the upper section is attached to a tubular operating string 2 which extends to the ground surface. The lower end of the body section I is inwardly thickened and has 'th'downwardly flared guide 3 whereby the tool may be guided over the upper end of the pipe 4 stuck in a well. Above the guide 3 the body has i an internal, annular shoulder 5 on which an antifriction ring 6 is located which supports the helical spring 1.

.mally registers with the shoulder 5. end of the actuator is outwardly flared and formed with a curved'bearing surface [6. 20,

Ihe lower 'end' of the upper section la. forms an inside, annular shoulder'8 against which the inside anchor-ring9 abuts. The lower'endsof the 'fiexible "arms ID are secured to thisanchor ring and the 'upper ends of these arms converge 5 inwardly. The arms will expand upon downward movement of the tool over the pipe so as to readily pass-over pipe couplingsas l I but upon upwardtmovement of the toolxthe upper ends of said ar ms'will engageunderneath the coupling. 10

Seated upon the upper end of the spring I there is an anchor ring l2 and between the rings 9 and [2 there is an antifriction ring 13.

Within the spring 1. and attached at its upper to the anchor ring 12 there is a' sleeve-like cutter 15 actuator l4 whose lower endis outwardly thickened forming the annular shoulder l5 which-nor- The lower Beneath the shoulder. 5 the cutter body has theinside, vertical grooves forming cutter guides- I! whose upper ends have the inwardly curved bearingsrsurfaces l8 and :wh'oselower ends are formed'with the arcuate'seats I9. Cutters 20 are 25 located in said .guidesi *The'ir lower ends are curved'to conform to the shape of the seats. I9 and are pivoted on the transverse-pins 2i. The cutters are normally held retracted; or Withdrawn into the guides, as shown in Figure 1, bythe 30 fiat pressure springs 22. The upper ends of the cutters areinwardlycurved andbear against the curvedsurface' I6 and terminate in the forwardly r directed cuttingxpoints 23.

In operation the :tool may be lowered'into'the 35 well-"over-the pipe l to be cut. When the desired location has-been reached the tool may be pulled upwardly until the upper ends of the arms engage underneath the next collar above. Upon a further upward pull on the string 2 the body 49 of the cutter Will move upwardly relative to the ring assembly 9, l2, l3 thus placing the spring I under compression. The actuator I4 however, will be held against upward movement. The cutters 20 will move upwardly with the body and 5 their outer curved surfaces will frictionally engage, and be forced inwardly by, the curved face l6 of the actuator thus forcing the cutters inwardly into cutting relation with the pipe 4 and upon rotation of the tool the pipe will be sev- 50 cred as shown in Figure 3. As the tool rotates the friction of the cutters against the lower end of the actuator will hold said actuator against rotation so as to prevent undue wear on the lower end of the actuator and on the cutters. 55

When the pipe has been cut the cut off section may be withdrawn with the tool from the well. If it is desired, at any time, to lower the tool relative to the pipe 4 it may be moved downwardly thus relieving the compression on the spring 1 and the cutters 20 will be released from the pipe 4 and moved back into the guides IT by the pressure of the springs 22. Upon such downward movement of the body the expansion of the spring I will cause the actuator [4' to assume its original position as shown in Figure 1.

An illustration of the tool is shown in the drawing but it is obvious that mechanical changes may be made therein within the scope of the appended claims.

What I claim is:

1. An outside pipe cutter adapted to cut by rotation and shaped to telescope over a pipe in a well and comprising a body, an inside shoulder in the body, a yieldable member supported on said shoulder, a ring assembly supported on said yieldable member, means on the assembly arranged to be expanded by and to pass over pipe couplings upon downward movement of the body and engageable with a pipe coupling to hold the assembly stationary upon upward movement of the body and to thereby place the yieldable member under compression, inwardly movable cutting means in the body, a cutter actuator depending from the ring assembly and engageable with the cutting means to move the same inwardly into cutting relation with the pipe upon upward movement of the body.

2. An outside pipe cutter shaped to telescope over a stuck pipe in a well and comprising a cutter body, cutters pivoted in the body, an inside shoulder in the body above the cutters, a coil spring supported by said shoulder, annular anchoring means in the body supported by the spring, means attached to the anchoring means and arranged to be expanded by outside couplings on the pipe upon downward movement of the body, and engageable underneath an outside coupling on the pipe upon upward movement of the body to place said spring under compression, a cutter actuator within the spring and supported thereby and having an annular lower end face engageable behind the cutters to move them inwardly upon upward movement of the body relative to the pipe.

3. An outside pipe cutter adapted to cut by rotation and shaped to telescope over a pipe stuck in a well bore and comprising a tubular body having an inside, annular shoulder, a lower ring on the shoulder, a spring on said ring, an upper ring assembly in the body supported by said spring, a cutter actuator depending from said assembly within said spring and having a lower external shoulder on which the lower ring rests, pipe engaging means supported by said upper ring assembly and expansible to pass over outside couplings on the pipe upon downward movement of the body and engageable with an external shoulder on the pipe whereby upon upward movement of the body the spring will be placed under compression, inwardly movable cutting means pivoted in the body and engageable with the lower end of the actuator to move the cutters inwardly, into cutting relation with the pipe, upon upward movement of the body relative to the pipe.

4. An outside pipe cutter adapted to out by rotation and shaped to telescope over a pipe stuck in a well bore and comprising a tubular cutter body having an inside annular, lower shoulder, alower anti-friction ring on the shoulder, a coil spring on the ring, an inside annular downwardly facing upper shoulder in the body, an am chor abutting said upper shoulder, inwardly converging flexible arms whose lower ends are secured to the anchor ring and whose upper ends are free, said upper ends being expansible outwardly to pass freely over outside couplings on the pipe upon downward movement of the body and to engage underneath a coupling upon upward movement of the body, an anchor ring supported on said spring, an intermediate anti-friction ring between said anchor rings, a sleeve-like cutter actuator within the spring whose upper endis attached to the lower anchor ring and whose lower end is outwardly thickened forming an annular shoulder which normally registers with the lower shoulder in said body, said lower end of the actuator being outwardly flared, and formed with a curved bearing surface, said body having inside vertical grooves forming cutter guides and whose upper ends have inwardly curved bearing surfaces and whose lower ends are formed with arcuate seats, cutters located in said guides whose lower ends are curved to conform to the shape of said seats and are pivoted in said guides, pressure springs normally holding the cutters retracted, the upper ends of the cutters being inwardly curved and bearing against the curved surface of the actuator and terminating in inwardly directed cutting points, whereby upon upward movement of the body and the engagement of said arms with a coupling the coil spring will be placed under compression and the cutters will be moved to cutting relation with the pipe to sever the same upon rotation of the body.

GEORGE A. LOWREY. 

